The present invention relates to a method to improve gramophone records or, in particular, to a method for improving the surface properties of gramophone records fabricated with a vinyl chloride based synthetic resin.
As is known, most of today's gramophone records are made of thermoplastic synthetic resins. Such records typically include vinyl chloride based resins such as a copolymeric resin of vinyl chloride and vinyl acetate.
In addition to rather weak resistibility to wear and tear, one of the faults of the gramophone records of vinyl chloride based resins is the accumulation of an electrostatic surface charge which attracts floating dust particles in the air. This phenomenon causes soiling of the record surface and rapidly increases noise generation upon repeated playing of the records.
Various attempts have been made to devise an effective way or method to improve the surface properties of the gramophone records made of vinyl chloride based synthetic resins, including several chemical means with which the electrostatic charge on the surface can be reduced and by which the mechanical strength or, particularly, the resistance of the surface against wear and tear can be enhanced in a relatively simple and convenient manner without substantially increasing the production costs of the gramophone records.
Despite intensive efforts toward the above end, no solution, economic or otherwise, has yet been found to the above problem to obtain durable benefits of the improvement of the surface properties of the gramophone records made from vinyl chloride based resins.
For example, effect against electricity static on the surface of the record is obtained, though temporarily, by spraying a certain surfactant containing solution on the record's surface. The durable effect against static, however, is very limited.